Update nokogiri
Update nokogiri

Current version has a vulnerability: https://groups.google.com/forum/#!topic/ruby-security-ann/aSbgDiwb24s

thoughtbot/hound,eliperkins/hound,yatish27/hound,q-centrix/hound,thoughtbot/hound,platanus/hound,yatish27/hound,platanus/hound,brgaulin/hound,alexeyzab/hound,eliperkins/hound,brgaulin/hound,brgaulin/hound,bronislav/hound,yatish27/hound,bronislav/hound,eliperkins/hound,eliperkins/hound,houndci/hound,thoughtbot/hound,houndci/hound,Koronen/hound,bronislav/hound,bronislav/hound,houndci/hound,Koronen/hound,platanus/hound,yatish27/hound,brgaulin/hound,platanus/hound,houndci/hound,q-centrix/hound,alexeyzab/hound,q-centrix/hound,alexeyzab/hound,Koronen/hound,Koronen/hound,thoughtbot/hound,alexeyzab/hound,q-centrix/hound